Composite resin material for repairing asphalt pavement defects and preparation method thereof

Abstract

The present invention relates to the technical field of polymer composite materials, and more particularly to a composite resin material for repairing asphalt pavement defects and a preparation method thereof. Aiming at the problem of poor adhesion between the patching material for asphalt pavement potholes and the joints between the old pavement and the old pavement, the present invention toughens and modifies epoxy resin to propose a composite resin material suitable for pavement repair. Acrylic resin and epoxy resin are blended and modified to obtain an epoxy acrylic composite resin. The rheological properties of the composite resin are analyzed, and the effects of different acrylic acid contents on the toughness of the composite resin are explored. The epoxy acrylic resin for repairing asphalt pavement defects proposed by the present invention has good toughness, a simple preparation process, good thermal stability when the material is coated at room temperature, and certain economical and practical properties.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer composite materials, and in particular to a composite resin material for repairing asphalt pavement defects and a preparation method thereof. Background Art

[0002] Asphalt pavement is a flexible pavement structure composed of an asphalt mixture and various base and cushion layers. Due to its advantages of good surface smoothness, easy construction and maintenance, and comfortable driving, it has become the predominant pavement type today. With the rapid development of the transportation industry and a surge in road traffic, asphalt pavements are bearing increasing vehicle loads and frequency of loading. Due to the combined effects of environmental factors and vehicle loads, asphalt pavements are experiencing cracks, potholes, rutting, and other defects before reaching their designed service life. These defects severely impact driving stability, safety, and comfort. The impact loads from vehicle jolts and vibrations caused by defective pavements can be 1.5-2.0 times greater than those on undamaged pavements. Surface water seeps into the pavement structure through defective areas, causing the surface material to loosen and peel, and the base material to soften and reduce its bearing capacity. This can lead to crack expansion, localized subsidence, or pothole expansion in asphalt pavements, shortening the road's service life and causing significant economic losses.

[0003] Asphalt pavement defects are becoming increasingly prominent, and improving asphalt pavement maintenance and repair technologies has become a key issue in road construction. Currently, most asphalt pavement maintenance and repair methods are emergency repairs, which are relatively low-cost and quick to construct. However, with the development of the road industry, asphalt pavement maintenance technology is shifting from emergency maintenance to preventive maintenance. Potholes, a typical asphalt pavement defect, seriously affect the smoothness and driving comfort of the road surface. Repairing potholes as soon as possible can effectively extend the service life of asphalt pavements. Hot-mix asphalt has high strength and good stability, and is highly compatible with existing pavement when used as a pothole repair material. However, due to environmental factors, construction cannot be carried out in winter and rainy seasons, and potholes in asphalt pavements cannot be repaired in a timely manner, affecting road traffic. Cold-mix asphalt does not require heating for use, can be spread at any time, and is easy to apply. It can be used for pothole repair operations in cold weather and rainy days. However, during the investigation of the current status of pothole repair, it was found that the common pothole repair materials have poor adhesion to the joints of the road surface, resulting in a decrease in the integrity of the original road surface. Rainwater, oil stains, etc. on the road surface penetrate through the joints of the new and old asphalt mixtures. After the repair, the potholes are prone to loosening and the repair materials fall off. During the braking process of the vehicle, secondary damage by shearing and squeezing occurs in a short period of time, and potholes appear on the road surface again, increasing the maintenance workload and maintenance costs.

[0004] To address the poor adhesion between pothole repair material and the existing pavement, a method often used in potting sealants for asphalt pavements is to create grooves in the joints between the new and old asphalt surfaces and then fill them with adhesive to improve adhesion. However, this method is complex and not very cost-effective. Sealing can be used to cover the repaired pothole joints, creating a "cap" to increase adhesion. However, existing sealing materials are brittle at low temperatures and lose their adhesion to the pavement in the summer heat, resulting in a short service life. Summary of the Invention

[0005] In view of the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a composite resin material for repairing asphalt pavement defects and a preparation method thereof. In order to improve the integrity of the repaired asphalt pavement, reduce the erosion of the roadbed and pavement by rainwater infiltration, and extend the service life of the repaired asphalt pavement, the present invention proposes a pavement resin coating with good flexibility and strong adhesion, and analyzes the thermal effect of its curing process.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] The first object of the present invention is to provide a composite resin material for repairing asphalt pavement defects, wherein the composite resin material is composed of the following raw materials in weight fractions: 100 parts of epoxy resin, 10-50 parts of acrylic resin, 2-5 parts of accelerator, 40-60 parts of curing agent, 0.1-0.3 parts of defoaming agent, and 7-10 parts of other additives.

[0008] Preferably, the composite resin material is composed of the following raw materials in weight fractions: 100 parts of epoxy resin, 30 parts of acrylic resin, 2-5 parts of accelerator, 40-60 parts of curing agent, 0.1-0.3 parts of defoaming agent, and 7-10 parts of other additives.

[0009] Preferably, the epoxy resin is bisphenol A type resin E-51, and the acrylic resin is BS-104-2.

[0010] Preferably, the accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

[0011] Preferably, the defoaming agent is SH-5500 defoaming agent.

[0012] Preferably, the curing agent is 593 type curing agent.

[0013] Preferably, the other auxiliary agent is HK-3050 polyurethane.

[0014] Another object of the present invention is to provide a method for preparing a composite resin material for repairing asphalt pavement defects, comprising the following steps:

[0015] (1) Weigh the following raw materials in parts by weight: 100 parts of epoxy resin, 10-50 parts of acrylic resin, 2-5 parts of accelerator, 40-60 parts of curing agent, 0.1-0.3 parts of defoaming agent, and 7-10 parts of other additives;

[0016] (2) After mixing and stirring the weighed epoxy resin and acrylic resin, other additives are added thereto and stirred continuously to form a mixed resin. Then, the accelerator and curing agent are stirred and poured into the mixed resin and stirred until they are fully mixed. Finally, a defoaming agent is added and stirred continuously for later use.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention relates to a composite resin material for repairing asphalt pavement defects and a preparation method thereof. BS-104-2 acrylic resin (BS) having a large molecular weight, good toughening effect and weather resistance is used to toughen and modify epoxy resin (EP) by physical mixing to synthesize a composite resin - epoxy acrylic resin (EAM), thereby preparing a resin coating material with good toughness and hardness.

[0019] 2. The present invention discloses a composite resin material for repairing asphalt pavement defects and a preparation method thereof. With increasing BS dosage, the tensile strength and elongation at break of EAM (pure EP) both increase first and then decrease. At an optimal BS dosage of 30 parts, the tensile strength increases by 88.43% compared to EAM0 (pure EP). The elongation at break of the specimens increases first and then decreases with increasing BS dosage. At 30 parts BS, the elongation at break of the EAM3 sample reaches a maximum of 37.8%. When the BS addition reaches 30 parts, the impact strength of EAM3 increases by 103.14% compared to pure EP.

[0020] 3. A composite resin material for repairing asphalt pavement defects and a preparation method thereof according to the present invention: When the BS addition amount is 30 parts, the EAM3 tensile strength is 27.7 MPa and the elongation at break reaches 38.24%, which are 88.43% and 4202% higher than those of EAM0, respectively. The fracture toughness of the resin reaches the best; at the same time, within the appropriate hardness range, the EAM3 impact strength increases by 103.14%, reaching a maximum value of 32.3 kJ / m 2 , its impact toughness has also been greatly improved.

[0021] 4. The epoxy acrylic resin for repairing asphalt pavement defects proposed in the present invention has good toughness and a simple preparation process. The construction process parameters of the resin can be effectively predicted by measuring the degree of curing reaction. The initial decomposition temperature of the resin is 101°C. When the material is coated at room temperature, the thermal stability is good, which can meet the use requirements of the resin in high temperature weather in summer and has certain economic practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The viscosity-temperature curves of the epoxy acrylic resins of Examples 1, 2, 3, 4 and 5 are shown;

[0023] Figure 2 Graphs showing the mechanical properties test results of Example 1, Example 2, Example 3, Example 4, and Comparative Example 1. (a) shows the tensile strength and elongation at break; (b) shows the impact strength and Shore hardness.

[0024] Figure 3 The DSC curves of EAM3 at different heating rates in Example 1 are shown;

[0025] Figure 4 This is the relationship curve between EAM3 conversion rate and temperature in Example 1;

[0026] Figure 5 The extrapolated straight line of the T-β linear fitting of Example 1;

[0027] Figure 6 The relationship curve diagram in Example 1, (a) is ln(β / T p 2 )-1 / T p Relationship curve; (b) lnβ-1 / T p Relationship curve; (c) Figure is ln(β / T 1.92 )-1 / T relationship curve;

[0028] Figure 7 is the ln(β / T of EAM3 in Example 1 α 1.92 )-1 / T α Relationship graph;

[0029] Figure 8 This is the E-α relationship curve in Example 1;

[0030] Figure 9 This is the TG curve of the EAM3 cured product in Example 1. DETAILED DESCRIPTION

[0031] The following is a detailed description of the preferred embodiments of the present invention with reference to the accompanying drawings.

[0032] Raw materials:

[0033] Epoxy resin: Sinopharm Chemical Reagent Co., Ltd.; acrylic resin: Sanmu Chemical Reagent Co., Ltd.; curing agent: Sinopharm Chemical Reagent Co., Ltd.; accelerator: Sinopharm Chemical Reagent Co., Ltd.; defoaming agent: Foshan Lixin Chemical Co., Ltd.

[0034] Example 1

[0035] A method for preparing a composite resin material for repairing asphalt pavement defects comprises the following steps:

[0036] (1) Weigh the following raw materials in parts by weight: 100 parts of bisphenol A epoxy resin E-51 (EP), 30 parts of BS-104-2 acrylic resin (BS), 3 parts of 2,4,6-tris(dimethylaminomethyl)phenol, 50 parts of 593 curing agent, 0.2 parts of SH-5500 defoaming agent, and 8 parts of HK-3050 polyurethane;

[0037] (2) After the weighed bisphenol A epoxy resin E-51 and BS-104-2 acrylic resin were mixed and stirred at room temperature for 20 minutes, HK-3050 polyurethane was added thereto and stirred for 10 minutes to form a mixed resin. Then, 2,4,6-tris(dimethylaminomethyl)phenol and 593 curing agent were stirred for 5 minutes. After being fully mixed, the mixture was poured into the mixed resin. After stirring for 5 minutes, a defoamer was added and stirred for 2 minutes before use. The sample was named EAM3.

[0038] Example 2

[0039] The preparation method is the same as that of Example 1, except that 30 parts of BS-104-2 acrylic resin are replaced by 10 parts of BS-104-2 acrylic resin. The sample is named EAM1.

[0040] Example 3

[0041] The preparation method is the same as that of Example 1, except that 30 parts of BS-104-2 acrylic resin are replaced by 20 parts of BS-104-2 acrylic resin. The sample is named EAM2.

[0042] Example 4

[0043] The preparation method is the same as that of Example 1, except that 30 parts of BS-104-2 acrylic resin are replaced by 40 parts of BS-104-2 acrylic resin. The sample is named EAM4.

[0044] Example 5

[0045] The preparation method is the same as that of Example 1, except that 30 parts of BS-104-2 acrylic resin are replaced by 50 parts of BS-104-2 acrylic resin. The sample is named EAM5.

[0046] Example 6

[0047] (1) Weigh the following raw materials in parts by weight: 100 parts of bisphenol A epoxy resin E-51 (EP), 30 parts of BS-104-2 acrylic resin (BS), 2 parts of 2,4,6-tris(dimethylaminomethyl)phenol, 40 parts of 593 curing agent, 0.1 parts of SH-5500 defoaming agent, and 7 parts of HK-3050 polyurethane;

[0048] (2) After weighing bisphenol A epoxy resin E-51 and BS-104-2 acrylic resin, they were mixed and stirred at room temperature for 20 minutes, and then HK-3050 polyurethane was added thereto and stirred for 10 minutes to form a mixed resin. Then, 2,4,6-tris(dimethylaminomethyl)phenol and 593 curing agent were stirred for 5 minutes. After being fully mixed, the mixture was poured into the mixed resin. After stirring for 5 minutes, a defoamer was added and stirred for 2 minutes before use.

[0049] Example 7

[0050] (1) Weigh the following raw materials in parts by weight: 100 parts of bisphenol A epoxy resin E-51 (EP), 30 parts of BS-104-2 acrylic resin (BS), 5 parts of 2,4,6-tris(dimethylaminomethyl)phenol, 60 parts of 593 curing agent, 0.3 parts of SH-5500 defoaming agent, and 10 parts of HK-3050 polyurethane;

[0051] (2) After weighing bisphenol A epoxy resin E-51 and BS-104-2 acrylic resin, they were mixed and stirred at room temperature for 20 minutes, and then HK-3050 polyurethane was added thereto and stirred for 10 minutes to form a mixed resin. Then, 2,4,6-tris(dimethylaminomethyl)phenol and 593 curing agent were stirred for 5 minutes. After being fully mixed, the mixture was poured into the mixed resin. After stirring for 5 minutes, a defoamer was added and stirred for 2 minutes before use.

[0052] Comparative Example 1

[0053] The preparation method is the same as that of Example 1, except that BS-104-2 acrylic resin is not added. The sample is named EAM0.

[0054] The test method of the present invention:

[0055] 1. Viscosity test

[0056] A Brookfield viscometer (NDJ-1D) was used to measure the viscosity of the mixed composite resin with temperature. The heating rate was 3°C / min and the test temperature range was 20-80°C.

[0057] 2. Tensile strength and elongation at break test

[0058] A universal testing machine (CMT5105) was used to test the tensile strength and elongation at break of the specimens according to GB / T2567-2021, with a tensile rate of 10 mm / min.

[0059] 3. Impact strength test

[0060] A simply supported beam impact testing machine (XCJD-50) was used to carry out an impact toughness test on the specimen strips according to the GB / T2567-2021 standard, with an impact velocity of 2.9 m / s.

[0061] 4. Shore hardness test

[0062] The hardness of the samples was tested using a Shore hardness tester (type LX-D). Three sets of data were tested for each sample and the average value was taken.

[0063] 5. Non-isothermal scanning calorimetry test

[0064] A differential scanning calorimeter (200F3) was used to track the resin curing reaction process. High-purity indium was used for temperature correction. 5 mg of acrylic-epoxy resin system samples were weighed in an aluminum crucible at intervals. The crucible was sealed in a high-purity nitrogen atmosphere and heated from 30°C to 250°C at different heating rates (5 K / min, 10 K / min, 15 K / min, and 20 K / min).

[0065] 6. Thermogravimetric testing

[0066] The temperature-mass loss analysis of the cured resin was performed using a thermogravimetric analyzer (TG209 F3). 2.5 mg of sample was placed in a crucible under a nitrogen atmosphere, the heating rate was 5 K / min, and the scanning range was 0-500 °C.

[0067] Results and Analysis

[0068] 1. Performance characterization of EAM

[0069] 1.1 Rheological properties of EAM

[0070] As a thermosetting resin, EP's viscosity changes with the cross-linking reaction during curing. BS has a low viscosity and can dilute the epoxy resin and extend the resin's applicability time during the curing construction process. Figure 1The viscosity-temperature curves of EAMs with different ratios for Examples 1-5 show that EAMs are viscous liquids at room temperature. The initial viscosity decreases with the addition of BS. From 20 to 43°C, the free groups in the system gain energy as the system temperature increases, increasing their reactivity and causing a significant decrease in the system's viscosity. From 43 to 68°C, the EAM viscosity fluctuates by approximately 200 mPa·s. Above 68°C, the rate of increase in EAM crosslinking exceeds the increased activity of molecular chain movement caused by the temperature increase, causing the system to enter a gel state and its viscosity to rise sharply. The viscosity of EAM5 remains stable after dropping to 200 mPa·s, demonstrating that EAM5 does not undergo a curing reaction. The wide temperature range during the transition from liquid to gel state facilitates the practical application of resin materials.

[0071] 1.2 Mechanical properties of EAM

[0072] Epoxy resin has poor toughness after curing and is prone to brittle failure, resulting in failure of the overall structure of the coating. Therefore, the resin coating is required to have a certain toughness and hardness after curing. Toughness is divided into fracture toughness and impact toughness. Fracture toughness, as a material's own characteristic, is a measure of the material's resistance to brittle failure; impact toughness indicates the material's ability to resist external impact. The present invention characterizes the toughness of the composite resin through three indicators: tensile strength, elongation at break, and impact strength. According to Figure 1 Four formulations, EAM1, EAM2, EAM3 and EAM4, were selected to prepare specimens. Their tensile mechanical properties were tested after curing at room temperature. EAM0 was used as a blank control group.

[0073] Figure 2 (a) Depicts the changing trends of tensile strength and elongation at break of EAM at different BS dosage levels. With the increase of BS dosage, the tensile strength and elongation at break of EAM first increase and then decrease. When the optimal BS dosage is 30 parts, the tensile strength is 88.43% higher than that of EAM0 (pure EP). The elongation at break of the specimen first increases and then decreases with the increase of BS dosage. The change curve is shown in Figure 2. Figure 2 (a) When the BS content is 30 phr, the EAM3 sample reaches a maximum elongation of 37.8%. When the BS content is increased to 40 phr, the tensile strength of the material decreases, as physical entanglement contributes to the tensile strength of the material, and the elongation at break begins to decrease.

[0074] Figure 2 (b) is a line graph showing the impact strength and Shore hardness of EAM at different formulation ratios. Adding BS to the epoxy resin matrix reveals that the impact strength of the EAM increases with increasing BS content. When BS is added at 30 phr, the impact strength of EAM3 increases by 103.14% compared to pure EP. Further additions of BS decrease the impact strength of the resin.

[0075] When the vehicle load directly contacts the asphalt pavement surface, it will cause obvious cracks in the pavement, forming a stress concentration phenomenon. Therefore, the preparation of the asphalt pavement pothole repair coating material of the present invention has certain requirements for toughness to alleviate the plastic deformation caused by vehicle load. When the BS addition amount is 30 parts, the tensile strength of EAM3 is 27.7MPa, and the elongation at break reaches 38.24%, which is 88.43% and 4202% higher than that of EAM0, and the fracture toughness of the resin reaches the best; at the same time, within the appropriate hardness range, the impact strength of EAM3 increases by 103.14%, reaching a maximum value of 32.3KJ / m 2 , and its impact toughness is also greatly improved. In summary, the toughness of the resin is optimal at this time and it has a certain hardness, which makes it very practical as a road coating.

[0076] 2. Characterization of EAM3 reaction heat and characteristic temperature

[0077] EAM3 non-isothermal DSC

[0078] The heat flow-temperature spectrum of EAM3 is as follows Figure 3 As shown, the heating rates are 5K / min, 10K / min, 15K / min and 20K / min respectively. Figure 3 EAM3 exhibits a single exothermic peak in the curing reaction at all heating rates, indicating a single curing mechanism and no significant side reactions. As the heating rate increases, the heat released per unit time increases while the relative curing time decreases. This delays the exothermic reaction in the resin system, shifting the curing reaction's onset temperature and exothermic peak toward higher temperatures.

[0079] 2.2. Changes in EAM3 conversion rate

[0080] By integrating the exothermic peaks of the curing reaction of EAM3 at different heating rates, the relationship curve between the conversion rate of EAM3 and the curing temperature can be obtained. Figure 4 . The resin conversion rate curve shifts toward high temperature as the heating rate increases. In the initial reaction stage, when α≤20%, heat cannot be transferred from the surface of EAM3 to the inside, there are fewer active groups in the resin, and the conversion rate increases slowly; in the rapid development stage of the reaction, when 20%≤α≤80%, the viscosity decreases, heat is transferred from the surface of EAM3 to the inside, the active groups increase significantly, the curing reaction rate increases sharply, and the conversion rate increases rapidly; in the completion stage of the reaction, when α≥80%, the crosslinking density of EAM3 gradually increases, the viscosity becomes larger, the movement of its internal active groups is hindered, and the conversion rate increases slowly. Because the synthesized EAM3 has a certain heat capacity and a low thermal conductivity, it is affected by the thermal hysteresis effect of the system. When the heating rate is accelerated, the temperature of the system will not change immediately. At this time, the conversion rate-temperature curve moves to the right (high temperature).

[0081] Table 1 Non-isothermal kinetic characteristic parameters of EAM3

[0082] β / (K / min) <![CDATA[T i / ℃]]> <![CDATA[T p / ℃]]> <![CDATA[T f / ℃]]> 5 87.3 145.2 186.3 10 95.3 157.2 205.6 15 103.9 164.7 221.1 20 108.0 175.2 238.3

[0083] In the table: β is the heating rate, K / min; T i is the starting temperature, °C; T p is the peak temperature, °C; T f is the termination temperature, ℃.

[0084] 2.3.EAM3 characteristic temperature analysis

[0085] The heating rate has a great influence on the curing reaction temperature of the system, and the resin is usually in a constant temperature state during actual use. In order to eliminate the influence of the heating rate change on the reaction heat, the T i 、T p and T f Drawn on Figure 5 The approximate gelation temperature (T) under the condition of β = 0 K / min was obtained by T-β extrapolation method. i0 ), curing temperature (T p0 ) and post-processing temperature (T f0 ), which are 80.95℃, 136.20℃ and 169.95℃ respectively.

[0086] comprehensive Figure 5 Extrapolate the straight line to get T p0 、T f0 Due to the influence of internal heat accumulation in the resin during actual application, the actual curing temperature of EAM3 is slightly lower than 136.20°C. The present invention selects 130°C as the curing temperature and 150°C as the post-curing temperature. During the actual curing reaction, the resin system has low thermal conductivity, the temperature rise rate is too rapid, and the system temperature field is uneven. This causes uneven shrinkage of the EAM during curing, which in turn causes internal stress and material deformation. In severe cases, debonding and cracking may occur, thus affecting the service life of the material. The present invention adopts a curing method of 130°C / 100min + 150°C / 30min. After curing EAM3 at 130°C for 100 minutes, the temperature is raised to 150°C and the curing time is extended by 30 minutes. This reduces the internal stress during curing and enables the system to achieve optimal curing performance. This theoretical calculation value provides an important basis for determining the actual curing process parameters of EAM3.

[0087] 3. EAM3 curing kinetics model

[0088] The purpose of analyzing and predicting thermal activation reactions is to derive a comprehensive description of the reaction process that is applicable to various thermal treatment methods (including linear heating and other non-isothermal treatment methods). Based on the different temperature dependencies of thermal activation reactions, the conversion rate during the reaction process can be simplified and the reaction rate can be expressed as follows:

[0089]

[0090] Where: E is the activation energy of the reaction, KJ / mol; A is the pre-exponential factor, min -1 .

[0091] 3.1 Kissinger method

[0092] The Kissinger method assumes that the reaction temperature is highest at the peak temperature of the thermal analysis curve and is not affected by the heating rate. Its n-order reaction model is as follows:

[0093]

[0094] Where: R is the molar gas constant, 0.00831KJ / (mol·K)

[0095] According to Table 1, ln(β / T p 2 )-1 / T p Relationship curve and linear fitting, such as Figure 6 As shown in (a), E is 66.15 kJ / mol from the slope of the straight line, and A is 4.46×10 7 .

[0096] The reaction order n is determined by the Crane method. The Crane formula is (Equation 3.3):

[0097]

[0098] Plot lnβ-1 / T p The relationship curve is fitted linearly, such as Figure 6 As shown in (b), substituting E = 66.15 kJ / mol, the reaction order n is 0.90.

[0099] Substituting the obtained parameters into the n-order reaction kinetics model and performing integral transformation, the relationship between α and t, T is obtained (3.4):

[0100]

[0101] Where: α is the conversion rate, %; t is the curing time, min; T is the curing temperature, K.

[0102] As can be seen from equation (3.4), the conversion rate increases with increasing curing temperature and extending curing time. Substituting the curing temperature of 403.15K, or 130°C, into equation (3.4), we can see that the conversion rate reaches 99.9% after 100 minutes.

[0103] 3.2. Starink method

[0104] The Starink equation uses multiple scan rates and constant conversion rates to obtain activation energy. The general formula under non-isothermal conditions is:

[0105]

[0106] Plot ln(β / T of EAM3 1.92 )-1 / T relationship curve, such as Figure 6 (c) The slope of the fitting curve is -1.0008E / R, which indicates that the activation energy E of the system at the peak temperature is 66.39KJ / mol.

[0107] Table 2 EAM3 curing reaction kinetic parameters

[0108]

[0109] Note: E ave is the average value of the activation energy.

[0110] ln(β / T α 1.92 )-1 / T α The linear fitting line is as follows Figure 7 As shown. According to the calculation results, a line graph of activation energy E at different conversion rates can be drawn, see Figure 8 As the EAM3 conversion rate increases, the broken line shows a trend of first gently rising and then rapidly declining. When α ≤ 0.4, EAM3 absorbs energy more slowly due to its own thermal hysteresis, and the activation energy value stabilizes between 65 and 66 kJ / mol. At this point, the activation energy is high and the trend is relatively gentle. As the conversion rate increases, the EAM3 curing degree increases, the viscosity rises rapidly, and the reaction begins to be dominated by diffusion control, with the activation energy showing a clear downward trend.

[0111] 4. Thermal stability analysis of EAM3

[0112] The thermal stability of a polymer material is defined as its resistance to thermal deformation and thermal decomposition. This test uses thermogravimetric analysis to characterize the thermal stability of the EAM3 cured product by measuring the relationship between mass and temperature. Taking into account the inherent thermal hysteresis of the cured product, a heating rate of 5 K / min was used. Figure 9The following is a graph of the TG curve of the cured product under a nitrogen atmosphere. The thermal weight loss of the EAM3 cured product can be divided into three stages. In the 0-101°C range, the sample's weight loss rate is lowest, indicating that the cured product is in a glassy state and exhibits good thermal stability. In the 101-353.9°C range, the sample's weight loss curve is gentle, but significant mass loss begins. Above 101°C, the resin material transitions to a highly elastic state, where residual solvent evaporates, the network structure is slightly disrupted, and the weight loss is minimal. As the temperature continues to rise, most organic matter begins to oxidatively decompose between 200 and 300°C, increasing the weight loss and affecting thermal stability. The weight loss curve is relatively gentle in the early stages, but suddenly changes at 353.9°C, indicating thermal degradation and the transition from a highly elastic state to a viscous flow state. In the 353.9-500°C range, the sample's mass loss reaches 72.91%, marking the complete loss of mechanical properties. The measured glass transition temperature of the cured product is well above the service temperature of this composite resin, indicating good thermal stability in practical applications.

[0113] In summary, to extend the service life of asphalt pavement repair materials and considering the shortcomings of existing pavement repair materials, a composite resin for pavement repair was prepared by synthesizing EAM using BS-modified EP. Based on viscosity-temperature curve test results of resins with different ratios, suitable composite resin formulas EAM0, EAM1, EAM2, EAM3, and EAM4 were obtained. Performance testing yielded the following conclusions:

[0114] (1) By testing the tensile strength, elongation at break, impact strength grade and Shore hardness properties of five composite resins, the formula EAM3 with the best toughness was obtained.

[0115] (2) Based on the characteristic temperature of EAM3 obtained by non-isothermal differential scanning calorimetry, it is recommended that the curing process of the resin during on-site construction be 130℃ / 100min+150℃ / 30min.

[0116] (3) The Kissinger method, Crane method, and Starink method were used to obtain the average activation energy of EAM3, which was 67.43 kJ / mol, and the reaction order was 0.90, and a system reaction model was established.

[0117] (4) Thermogravimetric analysis showed that the mass loss of EAM3 cured product in the range of 0-101°C was only 0.1%.

[0118] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A composite resin material for repairing asphalt pavement defects, characterized in that: The composite resin material is composed of the following raw materials in parts by weight: 100 parts of epoxy resin, 30 parts of acrylic resin, 2-5 parts of accelerator, 40-60 parts of curing agent, 0.1-0.3 parts of defoaming agent, and 7-10 parts of other additives; The epoxy resin is bisphenol A type resin E-51, and the acrylic resin is BS-104-2; A method for preparing a composite resin material for repairing asphalt pavement defects comprises the following steps: (1) Weigh the following raw materials in parts by weight: 100 parts of epoxy resin, 30 parts of acrylic resin, 2-5 parts of accelerator, 40-60 parts of curing agent, 0.1-0.3 parts of defoaming agent, and 7-10 parts of other additives; (2) After mixing the weighed epoxy resin and acrylic resin, add other additives and continue stirring to form a mixed resin. Then stir the accelerator and curing agent until they are fully mixed and pour them into the mixed resin and stir. Finally, add the defoaming agent and continue stirring for later use.

2. The composite resin material for repairing asphalt pavement defects according to claim 1, characterized in that: The accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

3. The composite resin material for repairing asphalt pavement defects according to claim 1, characterized in that: The defoaming agent is SH-5500 type defoaming agent.

4. The composite resin material for repairing asphalt pavement defects according to claim 1, characterized in that: The curing agent is 593 type curing agent.

5. The composite resin material for repairing asphalt pavement defects according to claim 1, characterized in that: The other auxiliary agent is HK-3050 polyurethane.

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